### Civil Engineering - Strength of Materials MCQs Part 2

1. Pick up the correct statement from the following :

A.
A ductile material has large plastic zone
B.
A brittle material has no plastic zone
C.
A rigid material has no plastic zone
D.
All the above.

2. The number of points of contraflexure in a simple supported beam carrying uniformly distributed load, is

A.
1
B.
2
C.
3
D.
0

3. The maximum bending moment due to a moving load on a simply supported beam, occurs

A.
at the mid span
B.
at the supports
C.
D.
anywhere on the beam
E.
none of these.

4. A three hinged parabolic arch hinged at the crown and springings, has a horizontal span of 4.8 m and a central rise of 1 m. It carries a uniformly distributed load of 0.75 tonne per metre over half left hand span. The horizontal thrust at the support will be

A.
10.8 tonnes
B.
1.08 tonnes
C.
1.8 tonnes
D.
0.8 tonnes
E.
none of these.

5. The length of a column which gives the same value of buckling load by Euler and Rankine-Gordon formula, is equal to

A.
B.
C.
D.
none of these.

6. The length of a column, having a uniform circular cross-section of 7.5 cm diameter and whose ends are hinged, is 5 m. If the value of E for the material is 2100 tonnes/cm2, the permissible maximum crippling load will be

A. 1.288 tonnes
B. 12.88
C. 128.8 tonnes
D. 288.0
E. none of these.

7. If a three hinged parabolic arch carries a uniformly distributed load on its entire span, every section of the arch resists.

A. compressive force
B. tensile force
C. shear force
D. bending moment.

8. In a three hinged arch, the shear force is usually

A. maximum at crown
B. maximum at springings
C. maximum at quarter points
D. varies with slope.

9. An arch may be subjected to

A. shear and axial force
B. bending moment and shear force
C. bending moment and axial force
D. shear force and thrust
E. thrust, shear force and bending moment.

10. The law which states, "within elastic limits strain produced is proportional to the stress producing it", is known as

A. Bernoulli's law
B. Stress law
C. Hooke's law
D. Poisson's law
E. none of these.

11. A simply supported beam of span L carries a uniformly distributed load W. The maximum bending moment M is

A.
B.
C.
D.
E.

12. A cantilever beam rectangular in cross-section is subjected to an isolated load at its free end. If the width of the beam is doubled, the deflection of the free end will be changed in the ratio of

A. 8
B. 1/8
C. 1/2
D. 2
E. 3

13. The phenomenon of slow extension of materials having constant load, i.e. increasing with the time is called

A. creeping
B. yielding
C. breaking
D. none of these.

14. The direction of the reaction at support B of a truss shown in below figure will be

A. East of North
B. West of North
C. East of South
D. West of South
E. Vertical.

15. The reaction at support A of the beam shown in below figure, is

A. zero
B. 5 T
C. 10 T
D. 1 T
E. 4 T.

16. The maximum resistance against rotation, is offered by the weld at a point

A. most distant
B. least distant
C. at either end
D. centrally located.

17. For structural analysis of forces, the method refers to

A. moment-area-theorem
B. three-moment equation
C. Maxwell's reciprocal theorem
D. none of these.

18. The B.M. of a cantilever beam shown in below figure at A, is

A. zero
B. 8 Tm
C. 12 Tm
D. 20 Tm.

19. If a member carries a tensile force P on its area of cross-section A, the normal stress introduced on an inclined plane making an angle θ with its transverse plane, is

A.
B.
C.
D.
E.

20. The reaction at the supports will be vertical to the plane of the support if the frame structure rests on

A. roller supports
B. free supports
C. hinged supports
D. all the above.

21. A cylinder is said to be thin if the ratio of its thickness and diameter, is less than

A. 1/25
B. 1/20
C. 1/15
D. 1/10
E. 1/5

22. The shear force on a simply supported beam is proportional to

A. displacement of the neutral axis
B. sum of the forces
C. sum of the transverse forces
D. algebraic sum of the transverse forces of the section
E. curvature of the neutral axis.

23. An arch with three hinges, is a structure

A. statically determinate
B. statically indeterminate
C. geometrically unstable
D. structurally sound but indeterminate
E. none of these.

24. Stress in members of statically determinate simple frames, can be determined by

A. method of joints
B. method of sections
C. graphical solution
D. all the above.

25. While testing a cast iron beam (2.5 cm x 2.5 cm) in section and a metre long simply supported at the ends failed when a 100 kg weight is applied at the centre. The maximum stress induced is :

A. 960 kg/cm2
B. 980 kg/cm2
C. 1000 kg/cm2
D. 1200 kg/cm2.

26. For a channel section, the shear centre lies at a distance of

A.
B.
C.
D.

27. When equal and opposite forces applied to a body, tend to elongate it, the stress so produced, is called

A. shear stress
B. compressive stress
C. tensile stress
D. transverse stress.

28. Stress in a beam due to simple bending, is

A. directly proportional
B. inversely proportional
C. curvilinearly related
D. none of these.

29. A cantilever carrying a uniformly distributed load W over its full length is propped at its free end such that it is at the level of the fixed end. The bending moment will be zero at its free end also at

A. mid point of the cantilever
B. fixed point of the cantilever
C. 1/4th length from free end
D. 3/4th length from free end
E. half length from free end.

30. In rectangular columns (cross-section b x h), the core is a

A. rectangle of lengths b/2 and h/2
B. square of length b/2
C. rhombus of length h/2
D. rhombus of diagonals b/3 and h/3
E. none of the these.

31. The tensile force required to cause an elongation of 0.045 mm in a steel rod of 1000 mm length and 12 mm diameter, is (where E = 2 x 106 kg/cm2)

A. 166 kg
B. 102 kg
C. 204 kg
D. 74 kg

32. According to Unwin's formula, the diameter d of a rivet of plate of thickness t is :

A. d = 6.05 t
B. d = 1.5 t + 4
C. d = 5 t
D. d = t + 1.5

33. In a bar of large length when held vertically and subjected to a load at its lower end, its own-weight produces additional stress. The maximum stress will be

A. at the lower cross-section
B. at the built-in upper cross-section
C. at the central cross-section
D. at every point of the bar.

34. If a shaft is simultaneously subjected to a toque T and a bending moment M, the ratio of maximum bending stress and maximum shearing stress is

A.
B.
C.
D.
E.

35. Struts are load carrying members of a frame structure which are subjected to

36. A simply supported wooden beam 150 cm long and having a cross section 16 cm x 24 cm carries a concentrated load, at the centre. If the permissible stress ft = 75 kg/cm2 and fs = 10 kg/cm2 the safe load is

A. 3025 kg
B. 3050 kg
C. 3075 kg
D. 3100 kg.

37. If the normal cross-section A of a member is subjected to tensile force P, the resulting normal stress in an oblique plane inclined at angle θ to transverse plane will be

A.
B.
C.
D.

38. The nature of the stress in horizontal members of the truss shown in below figure may be

A. compressive
B. tensile
C. shear
D. zero
E. all the above.

39. A solid cube is subjected to equal normal forces on all its faces. The volumetric strain will be x-times the linear strain in any of the three axes when

A. x = 1
B. x = 2
C. x = 3
D. x = 4

40. The structure shown in below figure is stable, if

A.
B. x = 2y
C. x = y
D. 2x = y.

41. n and j are numbers of members and joints in a frame. It contains redundant members if

A. n = 2j - 3
B. n = 3j - 2
C. n < 2j - 3
D. n < j - 2
E. n > 2j - 3

42. The materials which have the same elastic properties in all directions, are called

A. isotropic
B. brittle
C. homogeneous
D. hard.

43. The greatest eccentricity which a load W can have without producing tension on the cross-section of a short column of external diameter D and internal diameter d, is

A.
B.
C.
D.
E.

44. In a three hinged arch, the third hinge is generally kept at

A. crown of the arch
B. midpoint of the crown and left support hinge
C. midpoint of the crown and right support hinge
D. none of these.

45. A bending moment may be defined as :

A. Arithmetic sum of the moments of all the forces on either side of the section
B. Arithmetic sum of the forces on either side of the section
C. Algebraic sum of the moments of all the forces on either side of the section
D. None of these.

46. The property of a material by which it can be beaten or rolled into thin plates, is called

A. malleability
B. ductility
C. plasticity
D. elasticity.

47. If a constant section beam is subjected to a uniform bending moment throughout, its length bends to

A. a circular arc
B. a parabolic arc
C. a catenary
D. none of these.

48. A simply supported beam (l + 2a) with equal overhangs (a) carries a uniformly distributed load over the whole length, the B.M. changes sign if

A. l > 2a
B. l < 2a
C. l = 2a
D. l = 4a
E. l = 3a.

49. The type of butt joints in common use, is :

A. single inverted V-butt joint
B. double V-butt joint
C. double U-butt joint
D. single V-butt joint.

50. For structural analysis, Maxwell's reciprocal theorem can be applied to :

A. plastic structures
B. elastic structures
C. symmetrical structures
D. all the above.